Located in Aghaglassan, County Donegal, this archaeological site sits on the edge of a cliff overlooking the Black River, surrounded by what is now well cultivated farmland. The mound itself has been extensively quarried for stone over the years, which suggests it may have originally been a cashel; a type of stone ringfort common throughout Ireland during the early medieval period.

Cashels were circular defensive structures built with dry stone walls, typically serving as fortified homesteads for farming families between roughly 500 and 1200 CE. The fact that this site provided a ready source of building stone for later generations points to substantial stone construction, rather than the earthen banks and ditches that characterised other types of ringforts. The strategic position above the Black River would have offered both defensive advantages and access to water, making it an ideal location for such a settlement.

Today, visitors to the area will find little to mark this piece of Donegal’s ancient past beyond the disturbed mound itself. The site was documented in the Archaeological Survey of County Donegal, compiled by Brian Lacey and his team in 1983, which catalogued field antiquities throughout the county from the Mesolithic period through to the 17th century. Though time and human activity have erased most physical traces of what once stood here, the location remains an intriguing reminder of the defensive settlements that once dotted Ireland’s landscape.